ASoC: spear: Use *-y instead of *-objs in Makefile

*-objs suffix is reserved rather for (user-space) host programs while
usually *-y suffix is used for kernel drivers (although *-objs works
for that purpose for now).

Let's correct the old usages of *-objs in Makefiles.
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Link: https://lore.kernel.org/r/20240507155540.24815-26-tiwai@suse.deSigned-off-by: Mark Brown <broonie@kernel.org>

sound/soc/spear/Makefile

 # SPDX-License-Identifier: GPL-2.0
 # SPEAR Platform Support
-snd-soc-spear-pcm-objs := spear_pcm.o
-snd-soc-spear-spdif-in-objs := spdif_in.o
-snd-soc-spear-spdif-out-objs := spdif_out.o
+snd-soc-spear-pcm-y := spear_pcm.o
+snd-soc-spear-spdif-in-y := spdif_in.o
+snd-soc-spear-spdif-out-y := spdif_out.o
 
 obj-$(CONFIG_SND_SPEAR_SOC) += snd-soc-spear-pcm.o
 obj-$(CONFIG_SND_SPEAR_SPDIF_IN) += snd-soc-spear-spdif-in.o